<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script>
        //双重for循环 语法结构
        // for (外层的初始化变量;外层的条件表达式;外层的操作表达式){
        //     for (里层的初始化变量;里层的条件表达式;里层的操作表达式){
        //         //执行语句;
        //     }
        // }
        //外层循环一次 里层循环全部
        //代码验证
        for (var i = 1; i <= 5; i++) {
            console.log('外' + i);
            for (var j = 1; j <= 5; j++) {
                console.log('里' + j);
            }
        }
    </script>
</head>

<body>

</body>

</html>